Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of goodwill & intangible assets

The following table presents an analysis of goodwill, intangible assets with an indefinite life and intangible assets with a definite life for the years ended December 31, 2017, 2016 and 2015:

(U.S. dollars in thousands)	Goodwill			Intangible assets with an indefinite life			Intangible assets with a definite life			Total
Balance at December 31, 2014	$	415,936		$	15,366		$	16,650		$	447,952
Additions	807,381			673,000			315,000			1,795,381
Amortization	—			—			(15,517		)	(15,517		)
Foreign currency translation	(9,687		)	(5,507		)	(2,356		)	(17,550		)
Balance at December 31, 2015	$	1,213,630		$	682,859		$	313,777		$	2,210,266
Additions	14,084			8,000			28,948			51,032
Amortization	—			—			(22,422		)	(22,422		)
Foreign currency translation	(14,190		)	(8,080		)	(12,953		)	(35,223		)
Balance at December 31, 2016	$	1,213,524		$	682,779		$	307,350		$	2,203,653
Amortization	—			—			(21,834		)	(21,834		)
Foreign currency translation	20,626			16,235			7,071			43,932
Balance at December 31, 2017	$	1,234,150		$	699,014		$	292,587		$	2,225,751

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

Future amortization expenses of current intangible assets are as follows and will amortize over a weighted average period of 16.7 years:

Year Ended December 31, (U.S. dollars in thousands)
2018	$	20,291
2019	20,041
2020	19,957
2021	19,957
2022	19,957
2023-2036	192,384
Total expected amortization expenses	$	292,587